Monday, December 24, 2012

It’s always confusing here when we talk about summer.The gringos usually mean June-August, the summer
holidays for universities in the north; the summer field season for
hard-working graduate students; the busy season for the field stations.

But here, for Panamanians, summer starts in the weeks before
or after Christmas.It’s not a date you
can find in the calendar. There’s no gradual spring warming.It switches almost from one day to the next.

What
happens is this…..the Inter-Tropical Convergence Zone (ITCZ) is a thin strip of
low pressure between two areas of high pressure, one in the subtropical part of
the northern hemisphere and the other in the southern hemispheres. You can see the ITCZ from satellite
photos. It’s the band of clouds and
storms swirling around the equator.
During the dry season the northern hemisphere areas of high pressure
push the ITCZ south keeping it south of Panama and we get blue skies and breezy
dry days. The rest of the year it is
closer to us and keeps things wet and cloudy.

Red arrow points to us in Panama, orange arrows show the
line of clouds and rain. Photo from NASA.

Biologically
this has large effects.In the dry
season it doesn’t rain for weeks or even months.Trees lose their leaves. Dry grassy areas
burn.Residents spend time watering
their lawns.

For
us marine biologists things are different. The strong winds cause upwelling of
cool water, so it’s cold for marine life in Panama. Plankton
blooms in the Bay of Panama. Tuna and dolphins arrive to take advantage of the little fish that
thrive in upwelling. And the animals we
work on in the intertidal have to cope with wild fluctuations between the cold
water and the scorching sun as the tide goes in and out.Click for more information about the ITCZ in the news

Saturday, December 15, 2012

I’ve been trying for a few months – with no success
- to photograph a grey-necked wood rail (Aramides cajaneus).

Or perhaps I should say I’ve been wanting to
photograph them, but my efforts so far – occasionally wandering around outside
with my point-and-shoot camera in hand - have not been adequate for the
task.But today I decided to get
serious.

These silly-looking birds are some of my
favorites.You would never know they are
there until they pop, unexpected for such large birds, out of the undergrowth.
They strut out with their tail pointed straight up, looking both jaunty and
alarmed.They are absolutely
charming.Early in the mornings and on
grey drippy days you can hear them calling.A loud, complicated squawky cackle (listen here).

Plenty of other animals sit still for their portraits in rail habitat

Grey-necked wood rails are easy to see at the
Bocas del Toro Research Station and I want to add them to the iNaturalist list we
have been developing for the local plants and animals. Last time I was here I
saw 4 – a mother and 3 almost full-grown chicks-walking single file along the
fence at the end of the property.They
must have known I didn’t have my camera.Later, on the same trip, they walked out from under the dining hall,
only feet from where I was hosting a VIP.They must have know I wasn’t prepared.

So I was ready. Getting up early, covered in
long sleeves and mosquito repellent (dawn and dusk; you might find rails but
you will certainly find sand flies, and mosquitos), I positioned myself on the
corner ramp of our new dormitory building.And waited… and waited…Nothing.

I returned to the house, showered, looked out of
the window and there they were!Just
long enough for me to fire off a couple of shots through the dirty window as they darted into the undergrowth
laughing at me.

Monday, December 3, 2012

Finding something you think is new is the easy part.Then the work really begins.Before any species can be named it is
important to demonstrate that it does not already have a name.This sounds straightforward but it’s actually
a lot like historical detective work.Frustrating,
fascinating, and under-appreciated by people who don’t do it themselves.

The first step is to find all of the names
that have been given to species in the genus Crepipatella.This includes
the currently recognized species, as well as any other species that have been
synonymized with them.Species are
synonymized when two different species are named but are later found to be the
same species.This was not uncommon in
the 1800s when access to publications was not as rapid as it is today. It also happens when different individuals of
one species look differen. For example males and females can look different and
could have been described as different species.

When two species are synonymized the oldest name is the one
that is used, and all of the younger names are considered “junior synonyms”.

When David and I started our search for names in 2009, two names, C. fecunda and C. dilatata, were in use in Chile. But it turned out that 14 species of Crepipatella were described from South
America in the 1800s.We knew the
species discovered by David was not the same as C. fecunda or C. dilatata,
but we had to check the 12 other species.

The text and a figure from the original species description of

Crepipatella nautiloides by Lesson in 1830.

We tracked down the original species descriptions, checked the associated figures, plates or illustrations – these often tell you much more than the short text - to determine if any of them matched our new species. And finally – if they still exist - we checked the type specimen (the example of the species to which the name is formally attached) or their photos to see if they can tell us something useful.

The problem for us was that the old species descriptions are
mostly based on shells, but our species show diagnostic genetic and
developmental differences from the other two.Luckily there is also a tendency for the shells to differ:Crepipatella
fecunda tends to have larger, more robust shells that are white on the
inside. Crepipatella dilatata tends
to have smaller streaky brownish-red shells and our species tends to have
glossy chestnut shells.But there is a
lot of variation in each species.

Based on the geographic locations of these old species –
some were collected 1000s of miles from the known range of our species – and the
shell color, we were able to eliminate all of the previously named species and
show that the species discovered by David more than 10 years ago really did
need to be named.

We chose the nameocculta – The Latin adjective for hidden.Since it looks just like the other Crepipatella species and has been hidden
in plain sight for 100s of years.

About Us

Research in the Collin Lab focuses on the evolution of life histories and development of marine invertebrates. Our current work uses marine slipper limpets (Calyptraeidae) to try to understand the evolutionary loss and possible reacquisition of feeding larvae.
The Collin Lab is located in Panama City, Panama, at the Smithsonian Tropical Research Institute's Naos Marine Laboratories, but our field work takes us to various other countries in the Americas.
Using our blog we hope to give you an introduction to the faces in the Collin Lab, as well as a taste of the kinds of projects we are working on and the adventures we have while doing them.
http://www.stri.si.edu/
http://www.stri.si.edu/sites/collinlab/
Some of this material is based upon work supported by the National Science Foundation under Grant Number (IOS 1019727). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.